vsphere-esxi-vcenter-server-55-storage-guide

Chapter 4 Configuring Fibre Channel Storage2 Check that all SAN components meet requirements.3 Perform any necessary storage array modification.Most vendors have vendor-specific documentation for setting up a SAN to work with VMware ESXi.4 Set up the HBAs for the hosts you have connected to the SAN.5 Install ESXi on the hosts.6 Create virtual machines and install guest operating systems.7 (Optional) Set up your system for VMware HA failover or for using Microsoft Clustering Services.8 Upgrade or modify your environment as needed.N-Port ID VirtualizationN-Port ID Virtualization (NPIV) is an ANSI T11 standard that describes how a single Fibre Channel HBAport can register with the fabric using several worldwide port names (WWPNs). This allows a fabricattachedN-port to claim multiple fabric addresses. Each address appears as a unique entity on the FibreChannel fabric.How NPIV-Based LUN Access WorksNPIV enables a single FC HBA port to register several unique WWNs with the fabric, each of which can beassigned to an individual virtual machine.SAN objects, such as switches, HBAs, storage devices, or virtual machines can be assigned World WideName (WWN) identifiers. WWNs uniquely identify such objects in the Fibre Channel fabric. When virtualmachines have WWN assignments, they use them for all RDM traffic, so the LUNs pointed to by any of theRDMs on the virtual machine must not be masked against its WWNs. When virtual machines do not haveWWN assignments, they access storage LUNs with the WWNs of their host’s physical HBAs. By usingNPIV, however, a SAN administrator can monitor and route storage access on a per virtual machine basis.The following section describes how this works.When a virtual machine has a WWN assigned to it, the virtual machine’s configuration file (.vmx) isupdated to include a WWN pair (consisting of a World Wide Port Name, WWPN, and a World Wide NodeName, WWNN). As that virtual machine is powered on, the VMkernel instantiates a virtual port (VPORT)on the physical HBA which is used to access the LUN. The VPORT is a virtual HBA that appears to the FCfabric as a physical HBA, that is, it has its own unique identifier, the WWN pair that was assigned to thevirtual machine. Each VPORT is specific to the virtual machine, and the VPORT is destroyed on the host andit no longer appears to the FC fabric when the virtual machine is powered off. When a virtual machine ismigrated from one host to another, the VPORT is closed on the first host and opened on the destinationhost.If NPIV is enabled, WWN pairs (WWPN & WWNN) are specified for each virtual machine at creation time.When a virtual machine using NPIV is powered on, it uses each of these WWN pairs in sequence to try todiscover an access path to the storage. The number of VPORTs that are instantiated equals the number ofphysical HBAs present on the host. A VPORT is created on each physical HBA that a physical path is foundon. Each physical path is used to determine the virtual path that will be used to access the LUN. Note thatHBAs that are not NPIV-aware are skipped in this discovery process because VPORTs cannot beinstantiated on them.VMware, Inc. 41